Chilicola setosicornis Packer

Packer, Laurence & Genaro, Julio A., 2007, Fifteen new species of Chilicola (Hymenoptera: Apoidea; Colletidae), Zootaxa 1468, pp. 1-55 : 47-50

Chilicola setosicornis Packer , n. sp.

( Figs. 16A–O )

Diagnosis. This is a somewhat isolated species, perhaps most closely related to Toro and Moldenke’s Heteroediscelis (Packer, in press). It can be most readily separated from all other Chilicola in the male, by the long setae towards the apices of the apical flagellomeres ( Fig. 16A ). The form of the hind trochanter is also unique ( Fig. 16D and E ). Females differ from other Chilicola with apical hair patches on the metasomal terga and unmodified hind tibial spurs by the comparatively deep depressions dorsal of the antennal socket, which seem to house the scape. Only one other species matches this description, and Chilicola neffi Toro and Moldenke , has deeper and narrower frontal depressions but the females can be instantly differentiated by the maroon coloured metasoma of C. neffi , as well as by the latter species’ smaller size and location in coastal Chile rather than montane northwest Argentina.

Description. Male: Length 6.0mm, forewing length 4.0mm, head width 1.4mm.

Colouration: Black-brown with following parts yellow: Basal portion of labrum (rest dark brown), mandible (apex dark brown), clypeus except adjacent to epistomal suture, mark on lower paraocular area up to level of ventral margin of supraclypeal area, apicoventral spot on hind tibia. Following parts orange: Ventral surface of antennal flagellum, dorsal and anterior surfaces of foretibia, forebasitarsus, forepretarsus, S2 and S3 orange anterior to submarginal zone and all of S6. Wing veins and tegula dark brown. T1 and T2 dark brown, narrowly orange anterior to translucent amber apical impressed areas.

Surface Sculpture: Labrum shining with dense punctures basally (i~d) sparsely punctate apically (i=2– 3d). Clypeus with punctures small and dense apically (i~d), sparser towards base. Supraclypeal and lower and upper paraocular areas with strongly imbricate microsculpture, appearing almost granular and with small, sparse, irregularly spaced punctures (i =1–5d). Upper paraocular area with larger punctures. Frons with punctures crowded and sharp edged, very variable in size; area immediately below lateral ocelli with few, large punctures. Vertex behind ocelli rugose, laterally with dense punctures. Genal area with weak, elongate punctures on longitudinally microstriate background, shiny. Pronotum and metanotum roughly and densely punctate (i<d). Mesoscutum and scutellum dull due to dense microsculpture. Mesoscutum densely and irregularly punctate, i<d medially, crowded around parapsidal lines and along extreme anterior margin, sparser elsewhere (i=1–1.5d). Scutellum with i~d. Dorsal surface of propodeum finely rugoso-reticulate, posterior and lateral surfaces weakly wrinkled, dorsolateral areas slightly more strongly roughened. Mesopleuron irregularly punctate, i=1–3d. Metasomal terga dull, with strong microsculpture and dense punctures, i<d, sparser on T4–T6; basal impressed areas of T2 and T3 transversely microstriate.

Pubescence: White except for long erect pubescence on head, mesosoma and metasomal terga very pale yellowish; somewhat woolly. Face with erect pubescence, <1MOD below antennae, <2.5MOD above. Genal beard well developed, 0.5MOD anteriorly, 1.5MOD posteriorly. F5–F10 with apicoventral patch of elongate setae increasingly numerous on more apical flagellomeres ( Fig. 16A ). Dorsal surface of thorax with sparse long hairs, 1–1.5MOD; mesopleuron and lateral surface of propodeum with denser, long hairs (1.5MOD).

Ventral surface of hind femur with short sparse hairs mesobasally and with few longer hairs on dorsal surface. T2 and T3 with entire broad basal hair bands filling basal depressions, T1–T4 with medially interrupted apical hair bands. S2 with dense pubescence, 0.5MOD medially, 1.0MOD laterally; S3 with lateral hair patches 1MOD.

Structure: Head: Longer than broad, length to breadth 49:45 ( Fig. 16A ). Labrum 4X as broad as long, apex only slightly convex. Clypeus broader than long (35:30), apical one fourth extending beyond lower ocular tangent, lacking median groove, somewhat flattened dorsally ( Fig. 16A ). Epistomal suture broadly expanded mesad of and below anterior tentorial pit to 3X width of pit, pit separated from epistomal suture by one pit diameter. Subantennal sutures convergent below. Supraclypeal area well-defined dorsally, slightly longer than apical breadth (17:14). Frons with depression mesad of inner margin of eye above antennae, areabetween median ocellus and supraclypeal area also weakly depressed. Frontal line carinate for lower 0.7 of distance between antennal socket and median ocellus. Facial fovea absent; inner margin of compound eye weakly emarginate. Eyes convergent below ( Fig. 16A ), UOD:LOD 55:40. IOC slightly more than OOC, 19:17. Head slightly developed above compound eyes, upper ocular tangent tangential to lower margin of median ocellus. Vertex strongly convex in anterior view, flat in profile, 1LOL; occipital margin sharp but not carinate. Antenna very long and thin, scape 3X as long as apical width and 3X as long as pedicel, pedicel longer than greatest width (10:7); F1 shorter than F2 (20:28); F2–F9 up to 4X longer than broad, dorsal surface slightly concave, increasingly so on more apical flagellomeres; F10 shorter, 0.75X as long as F8, with apical half slightly expanded; F11 reduced, oval, one quarter as long as F8. Malar space linear such that presence or absence of malar suture indetectable. Gena narrower than eye (22:28).

Mesosoma: Elongate , length to greatest depth 2:1. Pronotal collar moderate in length 1LOL. Episternal groove well developed, scrobal groove strong, and finely pitted behind scrobe, absent anteriorly. Dorsal area of propodeum subequal in length to scutellum (ratio of scutellum:metanotum:dorsal surface of propodeum 19:10:20); propodeal sulcus shallow, shiny, abruptly narrowed towards posterior margin of dorsal surface, well defined posteriorly. Hind trochanter with two apicoventral angles joined by carinate ridge, outer angle acutely pointed, 2X as long as inner one, which is broadly rounded ( Figs. 16D and F ). Hind femur broadly expanded, ventral surface strongly convex, length to depth 63:37 ( Fig. 16D ). Hind tibia expanded, ventral surface with transverse swelling at basal third that is narrowed to short point mesally, length to apical depth 56:23 ( Fig. 16E ). Hind tibial spurs unmodified. Hind basitarsus less than 4X as long as greatest depth, deepest near base, narrowing to apex. Hind tarsal claws bifid. Basal vein almost straight; stigma very slightly convex in marginal cell, ratio of its length to marginal cell apical to stigma 39:53; distal stigmal perpendicular crossing first submarginal crossvein; first recurrent vein interstitial with first submarginal crossvein.

Metasoma: T1 slightly longer than wide (58:54); T2–T4 strongly depressed basally; apical impressed areas of terga short, 0.2X as long as entire tegum. Sterna unmodified, gradulus of S2 with long posteriorly directed lateral portions, S3–S6 with large U-shaped gradular mark on each side, open posteriorly.

Terminalia : S7 with two pairs of lateral lobes; ventral lobe narrow and apically directed; dorsal lobe laterally oriented, abruptly narrowed at basal 0.25, with tuft of long setae near base and row of shorter setae to apex ( Fig. 16G ). S8 with apical process broadest subapically, posterior margin concave ( Fig. 16H ). Genitalia as in Figs. 16I and J . Gonobase short, with apicoventral process broadly concave. Volsella short and triangular, digitus small and digitus and cuspis angulate posteriorly. Gonostylus weakly demarcated from gonocoxites. Penis valve with two membranous lobes, inner one with very long attachment to valve, outer one apparently arising between inner and outer crests of penis valve near apex, curled around inner lobe.

Female. As in male except for normal secondary sexual characteristics and as follows: Length 5.9mm, forewing length 4.0mm, head width 1.35mm.

Colouration: Black with ventral surface of F3–F9 dusky orange. Wing veins and tegula brown. Marginal zones of terga translucent orange-brown basally, colourless apically.

Surface Sculpture: Microsculpture strong throughout; face with shallow, moderately sparse punctures, i~2d; larger and somewhat denser on upper paraocular area and vertex, i<d. Vertex with punctures irregular in size and spacing. Pronotum with shallow dense punctures, i<d. Mesoscutum and scutellum with fine, shallow, dense punctures, i=1–2d; finer and denser along anterior and posterior margins of mesoscutum and anterior portion of scutellum. Punctures of anterior margin of metanotum crowded, i~d elsewhere. Mesopleuron sparsely punctate, i=2–4d. Dorsal surface of propodeum finely reticulate, reticulations not reaching posterior margin, which is shiny like the lateral and posterior surfaces, dorsolateral areas shallowly punctate. Metasomal terga with very fine, weak punctures, i>d.

Pubescence: Hairs short and sparse, except on gena, frons, mesopleuron and lateral surface of propodeum 1–2MOD. Scopal hairs of hind tibia 2MOD. Sparse basal hair bands on T2 and T3 and apicolaterally on T2– T4. Scopa of S2 corbiculate, hairs long 2.5MOD, with branches only on anterior surface, scopal hairs of S3 somewhat shorter 2MOD.

Structure: Maxillary palpus with segments increasing in length and decreasing in breadth from first to last, 0.7X as long as prementum. Prementum 0.4X as broad as long, with fovea covering most of ventral surface, margins strongly carinate. Lacinia an elongate triangle, 4X as long as greatest breadth. Lorum poorly sclerotised, less than 0.33X as long as cardo. Clypeus with transverse apical depression for middle half of its width, extending one third below lower ocular tangent. Compound eyes less convergent below ( Fig. 16C ), UOD:LOD 52:40. IOC:OOC 17:14. Frons swollen midway between lateral ocelli and antennae, swellings delimiting medial margin of supra-antennal depression. Dorsal surface of propodeum shorter, ratio of length to scutellum, 18:22. Apical lunule of S5 broadly U-shaped, 2X as broad as long.

Sting apparatus: As in Fig. 16K–O . Lateral portion of marginal ridge of hemitergite 7 with two obtuse angles, one where margin of apodemal region meets ridge, second one just anterior to origin of lateral process; apodemes to spiracular atrium large ( Fig. 16K ). Hemitergite 8 with plate and apodeme subequal in size, anterior ridge of apodeme slightly sinuate, junction between plate and apodeme straight ( Fig. 16L ). First valvifer with dorsal and ventral processes equal in length. Second valvifer with pars articularis acutely angled, incisura postarticularis narrow and parallel-sided. Base of sting shaft with processus medianus moderately developed ventrally ( Fig. 16M ). Furcula with ventral arms somewhat narrow, widely spaced forming broad U; dorsal arm comparatively broad, abruptly narrowing to apex; sinuate and narrow in side view ( Figs. 16N and O ).

Material studied. Holotype male, allotype female, one male and four female paratypes: ARGENTINA: Salta, Cuesta de Obispo, 1km E. of Piedra de Molina, 25o11’152” S 0 65 o51’236”W, 3340m, 20.iv.2003, L. Packer; one female paratype, Salta, Cuesta Obispo, iii.1997, Fritz. All specimens except the one collected by Fritz were found as adults in hollow stems of an unidentified shrub except both males and one female that emerged later the same year from nests obtained at the site. The holotype, allotype and one female paratype are at MACN, the remaining paratypes are at PYU except Fritz’s specimen, which is at AMNH.

Etymology. The specific epithet refers to the setation on the more apical antennal flagella of the male.

Comments. This species generally agrees with that section of Toro and Moldenke’s subgenus Heteroediscelis that was subsequently sunk within Oediscelis by Michener, (1995), (i.e. those species possessing a highly modified hind femur and tibia in the males). It can be differentiated from these species by the long antennal flagellomeres and form of the hind tibia, which is considerably expanded, but unlike Heteroediscelis with an expanded hind tiba, it lacks an incision just before the apex. The antennae are more reminiscent of C. (Oediscelis) vernalis Philippi and C. (O.) lonco Toro & Moldenke , although these latter two species lack the setation. It would seem to be somewhat isolated morphologically.

This is another interesting new species of Chilicola discovered in and primarily known from specimens obtained from nests. Other examples of species known only from nests include several species of the subgenus Oroediscelis ( Michener 2000; L. Packer unpublished data), C. venticola Packer (Packer 2004) , C. (Anoediscelis) paramo González and Michener (González and Michener 2004) and also an undescribed species with affinities to C. inermis and C. mailen , known from a single gynandromorph collected by the senior author at the same locality and in stems of the same shrub that yielded the type series of C. setosicornis . Undescribed species in the subgenera Oroediscelis and Anoediscelis were also found in the same stems.

Figures

FIGURES 16 A – O. Chilicola setosicornis Packer, n. sp. Head of male: A. frontal view, B. lateral view. C. frontal view of female head. Male: D. Hind trochanter, femur and tibia, outer view. E. Hind tibia, oblique inner view. F. Hind trochanter, ventral view. G – J. Male terminalia. G. S 7. H. S 8. I. genital capsule Dorsal views are at the left. J. lateral view. K – O. Sting apparatus of female: K. hemitergite 7, L. hemitergite 8, M and N. Furcula dorsal and lateral view respectively. O. First and second valvifer with sting shaft. Stippling in A, B, D and E indicates pale colouration, elsewhere it indicates membranous regions. Sting apparatus of female.